#define _CRT_SECURE_NO_WARNINGS
#include<stdio.h>
swap(int** p1, int** p2)
{
	int* p = *p1;
	*p1 = *p2;
	*p2 = p;
}
int main()
{
	int a = 10;
	int b = 20;
	int* p1 = &a;
	int* p2 = &b;
	swap(&p1,&p2);
	printf("%p %p\n", &a, p2);
	printf("%p %p\n", &b, p1);
	return 0;
}